Automatically actuated flotation device



July 1, 1958 A. J. FRUENDT 2,840,833

AUTOMATICALLY ACTUATED FLOTATION DEVICE Filed NOV. 26, 1954 ADEL J. FRUENDT ATTORNEYS United States Patent AUTOMATICALLY ACT UATED FLOTATION DEVICE The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

The present invention relates to an automatically actuated flotation device and more particularly to an automatically actuated flotation device immediately operable in response to immersion in an activating fluid.

There are several known types of automatically actuated flotation devices which operate in response to immersion in an activating fluid such as water. However, all of these devices havea feature in common in that their operation depends upon generation of a pressurized gas by a chemical compound responsive to contact with an activating fluid. Consequently, their operation is characterized by a time delay between the initial immersion in an activating fluid and the inflation of the flotation equipment. This delay is further extended by the fact that many of these devices include spring biased valve means closing the chamber in which the gas generating chemical is enclosed so that the-activating fluid is not admitted to this chamber until the device is submerged far enough below the surface of the activating fluid that the critical pressure necessary to overcome the resistance of the biasing spring and open the valve may be developed.

The present invention contemplates a quick-acting automatically actuated flotation device instantaneously responsive to immersion in an activating fluid, whereby it becomes immediately effective to supply buoyant support for an object to which it is attached.

An object of the present invention is to provide a compact lightweight automatically actuated flotation device for ready attachment to an object to be supported thereby.

Another object is to provide an automatically actuated flotation device instantaneously responsive to a critical change in environmental conditions.

A further object is the provision of a flotation device including means for immediately releasing a compressed gas into an inflatable container from a relatively much smallerstorage container upon immersion of the device in an activating fluid.

A final object of this invention is to provide a flotation device instantaneously operable in response to a very small electrical power impulse.

The exact nature of this invention as well as other ob? jects and advantages thereof will be readily apparent upon consideration of the following description relating to the annexed drawings in which:

Fig. 1 shows a side elevation partially broken away of a preferred embodiment of the present invention, and

Fig. 2 is a longitudinal cross-sectional View showing the configuration of the expanding type non-explosive squib used in the present invention, both before and after it has been detonated.

Referring now to the'drawings, wherein like reference characters designate like or corresponding parts.through- 2,840,833 Patented July 1, 1958 2 out the several views, Fig. 1 shows an embodiment of the present invention suitable for attachment to an armately curved object and including an elongated generally cylindrical hollow body 11, a hollow container 13 securely attached to one end of the body 11 and comprising a battery housing, and a hollow open ended container 15 se- A curely attached to the other end of the body 11 with its open end remote from the point of attachment and comprising a storage chamber for an inflatable bladder. The assembly including the parts 11, 13, and 15 described above, must be provided with means for securely attaching it to an object for which this assembly is intended to provide buoyant support. This attachment may be by any suitable means appropriate to the particular application involved. One such means is illustrated in Fig. l as a pair of clamps 17, which are formed integrally with or fixedly secured to the body 11. The clamps 17 are shown secured by means of screws 18 to a curved member 81 represented in Fig. 1 by phantom lines and described in greater detail below.

The hollow body 11 is closed at one end by a first plug member 21 threadably engaged therewith which is hollow-and open at its inner end to form a cylinder arranged to receive a hollow piston member 23 having an enlarged head 25 sized to fit slidably within the body 11 and shaped to engage one end of a pressurized gas storage container 27 also slidably mounted within the body 11. The container 27 is preferably positioned within the body 11 by the combination of a shoulder 28 and a resilient annular member 29 effective both as a means for biasing the container into engagement with the head 25 of the piston member 23 and as a gas seal. The plug member 21 is also fitted with an outwardly projecting collar portion 31, fixedly secured thereto, which is arranged to support the hollow container 13 and the battery 37 mounted therein. The collar 31 is fitted at its open outer end with an electrically insulating member 33 arranged to support a pair of projecting electrical terminals 35 for engagement with suitable electrical receptacles in the battery 37 located in the container 13 which is secured to thecollar 31 by a suitable clamp assembly 39. The battery 37 may be retained in the container 13 by any suitable retaining means. However, since it is essential to successful operation of this device that the activat ing means be freely admitted to the battery, the container 13' may be open ended as shown in Fig. l with a readily removable lock wire 41 threaded through a plurality of openings in the container 13 adjacent its closed end to secure the battery. The electrical terminals 35 are connected by means of electrical conductors 43 to a nonexplosive expandable type squib 45 located within the chamber formed by the hollow plug member 21 and the hollow piston member 23 slidably mounted therein.

The other end of the body 11 is fitted with a second plug member threadably engaged therewith provided with a passage 53 extending through the plug from its inner end to its outer end and with a sharp projecting member 55 mounted upon its inner end. A projecting portion 57 is fixedly secured to the plug member 51 and extends outwardly therefrom to provide support for the container 15 secured to the projecting portion 57 by a suitable clamp assembly 39. The joint between the projecting portion 57 and the container 15 must be sealed against the escape of pressurized gas by any suitable seals such as the 0 rings 59 seated in suitable annular grooves in the periphery of the projecting portion 57 as shown in Fig. 1. The projecting portion 57 is provided with a passage 61 connecting with the passage 53 so that together these passages constitute a duct for the transmission of pressurized gas released from the container 27 to the inflatable bladder 65 stored in a collapsed cons dition within the container 15. The open end of the container may be closed by a movable cover 67 which may be provided with a recess in its inner surface to receive a die marker 69. The cover 67 is mounted so that it will be forced out of engagement with the container 15 as the bladder 65 is inflated, and to insure successful performance of this device an elongated tubular outlet 63 may be mounted upon the projecting portion 57 to extend the duct formed by the passages. 53 and 61 to a location within the container 15 immediately beneath the cover 67. With the bladder 65 connected to the free end of the tubular outlet 63, the initial phase of inflation of the bladder 65 will force the cover. 67 off the container and begin to draw the bladder out of the container.

A preferred embodiment of the squib 45 is shown in greater detail in the longitudinal cross-sectional view identified as Fig. 2 in which the dimension A indicates the original length of the non-explosive expandable type squib and the dimension B indicates the relatively greater length of the squib after it has been detonated.

It is to be understood that the battery 37 is of a suitable immersion type, preferably capable of long term dry storage without deterioration, yet instantaneously operable upon immersion in an activating fluid to generate, an electrical power impulse. For numerous useful applications presently contemplated the battery 37 may be a known type designed to be responsive to immersion in salt water, yet insensitive to fresh water.

The configuration illustrated in Fig. l is especially designed for attachment to the nose-ring of a sleeve type aerial target for supporting the target when it falls into the sea upon release from a towing aircraft. The broken away arcuate element 81 represented in Fig. 1 by phantom lines is a portion of a typical nose-ring of a sleeve target to which a towing bridle is attached by a plurality of connections one of which is represented at 82 in Fig. 1.

In operation, the present invention remains inoperable with all its parts arranged as shown in Fig. 1 so long as the object to which it is attached is exposed only to the atmosphere even when it includes clouds made up of fresh water particles. However, when an object with the present invention attached is immersed in salt water, this fluid immediately activates the immersion, type battery 37 by direct contact therewith causing the battery to generate an electrical impulse transmitted through the terminals and the conductors 43 to the squib 45 which is thereby detonated. The burning of the powder 71 generates a substantial pressure within the squib 45 causing it to expand from the configuration shown. in solid lines in Fig. 2 with its long dimension designated by the letter A to the extended configuration shown in dotted lines in Fig. 2 with its long dimension. designated by the letter B. This expansion of the squib .45, forces the piston member 23 to the right as shown in Fig. 1 relative to the hollow plug member 21 so that the. pressurized gas container 27 is forced to the right within the body 11 to, deflect the resilient seal 29 and engage the sharply pointed member 55. The member penetrates a. sealed opening in the casing of the container 27 to release the pressurized gas which upon its release from the container is confined within the body 11 and the projecting portion 57 by the seals 29 and 59 so that the gas is forced to travel through the tubular member 63 and into the inflatable bladder 65. As the bladder 65 is inflated it expands first adjacent the open end of-the container 15 and thereby forces the cover 67 containing the die-marker 69 out of engagement with the container 15. The pressurized gas continues to flow from the container 27 through the passages 53 and 61 and thence through the tubular member 63 until the inflatable bladder 65 is fully inflated outside of the container 15. With thebladder 65 fully inflated the device comprising the instant invention provides buoyant support suificient to float the object to which it is attached and thereby permit recovery of that object from the surface of the sea. The release of the die-marker 69 by inflation of the bladder 65 provides a ready means for locating the object supported by this device.

Thus, it may be seen from the foregoing description that the present invention provides a compact, reliable, automatically actuated floatation device instantaneously operable in response to immersion in an activating fluid to provide buoyant support for any object to which it is attached which would otherwise be submerged in such a fluid.

Obviously, many modifications and variations of the present invention are possible in the light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. In a flotation device including an environmentalcondition sensing signal generating means for producing an electrical impulse, fluid pressure release means including a hollow generally cylindrical elongated housing, a squib cylinder fixedly mounted in one end of said housing, a hollow piston slidably mounted within said squib cylinder, an electrically actuated expandable squib enclosed within the space bounded by said cylinder and said piston, an elongated pressurized fluid container mounted slidably within said housing adjacent said piston, a resilient biasing means mounted within said housing and arranged to bias said container into engagement with said piston, a sealed opening in the end of said fluid container remote from said piston, and a seal opening means fixedly mounted in the other end of the housing adjacent to the sealed opening in said container, where.- by expansion ofthe squib overpowers the biasing effect of said resilient biasing means to produce sliding movement of the piston and the container adjacent thereto so that the sealed opening in the container is forced against the, fixed seal opening means to break the seal and release the pressurized fluid within said container.

2. An automatically actuated fluid pressure releasing device comprising an electrical signal generating means operable in response to a critical change in environmental conditions, and a pressurized fluid release means, said pressurized fluid release means including a generally cylindrical hollow elongated housing, a hollow squib cylinder fixedly mounted in one end of said housing, a hollow piston slid-ably mounted within said squib cylinder, an expandable squib enclosed within the space defined by said cylinder and said piston, an elongated pressurized fluid storage container mounted slidably within said housing adjacent said piston,.a resilient biasing means mounted fixedly within said housing adjacent the end of said container remote from said piston and. arranged to bias said container into engagement with said piston, asealed opening in the end of said fluid container remote from said piston, and a seal openingmeans fixedly mounted in the other end of the housing adjacent the sealed opening of said container, whereby expansion of the squib in response to a signal from the signal generating means overcomes the biasing effect of said resilient biasing means to produce sliding movement of the piston and the adjacent container in order to force the sealed opening in the container against the adjacent seal opening means to rupture the seal and release the pressurized fluid from said container.

3. An automatically actuated flotation device comprising an elongated housing assembly including a first openended container at one end, asecond open-ended container at the other end, and a closed chamber interposed between said first andsaid second open-ended containers, an electrical signal generating means operable in response to immersion in salt water mounted within said first container, a collapsed and folded inflatable bladder stowed in said second open-ended container, a pressurized fluid source means mounted within said closed chamber comprising a tank containing said fluid movable with respect to said closed chamber, means rigid with said chamber for releasing said fluid from said tank upon contact, and an electrically actuated expandable squib for moving said tank into contact with said releasing means, signal transmission means interconnecting said squib and said electrical signal generating means mounted within said first container, and fluid duct means interconnecting said pressurized fluid source means and the bladder stowed within said second container.

4. An inflation unit for an inflatable flotation device, comprising first and second cylindrical members joined at one end, battery means within said first cylinder member responsive to contact with salt Water for producing an electrical impulse, a non-explosive expandable squib located in said second cylinder member wired to said battery for actuation upon receipt of said impulse from said battery, pressurized fluid storage means located in said second cylindrical member mounted between said squib and a resilient retaining member supported by said second cylindrical member, a sealed outlet on said storage means, and puncture means mounted on said second cylindrical member facing said outlet for causing puncture thereof when said storage means is urged by said squib upon expansion against said resilient retaining member to release the pressurized gas contained therein.

5. The inflation unit of claim 4 in which a third cylindrical member is joined at one end to the free end of said second member containing a deflated bladder, means to transfer the released pressurized gas to the interior of said bladder, and slidable means mounted in the outer end of said third member for permitting said bladder to expand to its full length when inflated.

.6. In a flotation device, a first hollow elongated means containing an inflatable bladder, a second hollow elongated means joined end to end With said first elongated means containing pressurized fluid storage means movably supported and having a sealed outlet, means for delivering said fluid from said storage means to said bladder upon opening of said sealed outlet, release means adjacent to and capable of opening said sealed outlet upon contact therewith, and a third hollow elongated means connected end to end With said second elongated means at the end opposite said first elongated means containing means responsive to a predetermined condition for urging and maintaining said storage means in contact with said release means for opening said outlet and permitting the fluid therein to escape into said delivering means for inflating said bladder, said first, second, and third elongated means forming a generally elongated structure suitable for use as an automatically actuated, quick-acting flotation device.

References Cited in the file of this patent UNITED STATES PATENTS 7 1,367,225 Barker Feb. 1, 1921 1,798,430 Markens Mar. 31, 1931 1,956,494 Dagn-all et al Apr. 24, 1934 2,284,650 Grant June 2, 1942 2,378,924 Honegger et al. June 26, 1945 2,536,847 Harrow et al. Jan. 2, 1951 

